Method and apparatus for intercepting oil well casing gases during a welding operation



SUMMERS 2,175,137

E. G. IBTHOD AND APPARATUS FOR INTERCEPTING OIL WELL CASING GASES DURINGA WELDING OPERATION Filed March 11, 1939 Oct. 3; 1939.

Patented Oct. 1 939 I v UNITED. STATES PATENT wOFFlCE" METHOD ANDAPPARATUS FOR INTEBGEPT ING OIL WELL CASING GASES DURING A WEIDINGOPERATION Earl G. Summers, ClendeninQW. vs. v Application m 11, 19:9,Serial No. 201,312] a Claims. (01. 166-15) The present inventionconsists of a method and iswdished out, as indicated at 6. The head 5and apparatus for intercepting casing gases for is provided with anannulus 'Iwhich circumoil and gas wells during a welding operation, anscribes the dished out portion 6 and has mountobject of which is toprevent the rising gases of ed on the free face thereof an elasticgasket 8.

5 the well from reaching the area where the joints The gasket 8 isprovided with a central opening 6 of the inner casing pipes are beingwelded. through which the inner casing extends, the wall In modern welldrilling it is preferred to unite, of the opening snugly embracing theouter peon the Job, adjacent ends of the inner casing riphery of thecasing 4. The gasketis secured pipes by a welding operation but, becauseof the from displacement by a metal ring 9, the latter 10 fire hazard,this has heretofore been impractical. being superimposed on thegasketand provided 1 I have, after some experiment, found that the with anopening of a diameter co-extensive with present well drilling apparatus,with slight modithe diameter of the dished out portion 6 of thefication, may be employed to effectively" interbore of the head 5, atthe upper terminal of the cept gases rising from the well, both insideand latter. The-ring 9 is clamped to the gasket 8 outside of said casingandtobypass said gasesto and flange 1 by nuts and bolts In. It will, of16 a point remote fromthe well. course, be manifest that the gasket maybe re- ,It is an important object of the invention to placed'at theoption of the user. provide a method which is simple in operation Thehead 5 is provided with conduits or tubes yet effective to control theinflammable gases ll, extending laterally therefrom through which 20rising from the well, the apparatus used for gasesintercepted by thegasket 8 are vented at a 20 carrying out this method being likewisecharpoint remote from the wall.

acterized by simplicity, but positive in its opera- In order to preventinternal passage of gases tion to perform in accordance with theteachings throughthe casing 4, I provide a seal l2, which of theinvention. in the present instance is shown to consist of an In carryingout my invention I have found that inflated tube or bag which engagesthe inner wall 25 Y a preferred form consists of a method and apof'thecasing. Preferably the seal I! is of apparatus which will prevent thecasing. gases from preclable length so as to provide an internal sealrising above a predetermined point, means emof-sufiicient magnitude topositively prevent any ployed for this purpose being positionedinterpossibility of gas passing between the seal and 80 mediate thejoint of the pipes being welded and the wall of the. casing. I preferalso that the so outlets in the casing through which the casing innersea] II project below and above the outer gases are vented. seal orgasket during the welding operation of Other objects will be apparentfrom the 101- the first joint. Said inner seal remains. in the lowingdescription of the present preferred form first joint of the pipe. Ofcourse, gases rising 88 of the invention, taken in connection with thein the pipe 4 are intercepted'by the seal l2 and accompanying drawing,wherein: compelled to return to the bottom of the casing 4 Fig. 1 is aside elevatlonal view of apparatus and pass upwardly betweenthe casings4 and '3 employed for carryingout the present invention, for ultimateexpulsion from the casing head into parts thereof being broken away todisclose dethe conduits II. It is, of course, to be under- 40 tails ofthe specific internal and external sealing stood that although aninflated tube [2 is shown 40 means employed, and and described, I mayemploy other kinds of seals Fig. 2 is a plan view taken on the line 22of or plugs. Fig. 1, looking in the direction of the arrows. The firstjoint of the inner casing, which is to To illustrate the application ofmy invention, be welded, is indicated at l3, it being located just Ihave in the drawing, shown an outer oil well above the top of the innerseal It. This joint is 45 casing 3 and an inner casing 4 which may be ata point sufllciently above the gases to meof standard construction. Theouter casing is ent possibility of the latter igniting during theequipped with a head or frame 5 which isdewelding operation. pponoompletionof the weld, tachably engaged with the outer casing. The thesections of pipe going to make up the casing V internal diameter of theouter casing is in excess 4 are lowered into the well in a manifestmanner. 50

of the external diameter of the casing 4 to perin conjunction with theseal l2. Consequently mit the inner casing to pass freely therethroughthe seal 12 travels downwardly in the well with in a manner well knownin the art. Likewise the the first two pipe sections. Said seal remainsin inner diameter of the head 5 is of larger dia;m' this position untilthe first pipe section reaches eter than the external diameter of thecasing 4 the bottom of the well and correspondingly until the lastsection of pipehas been welded to its sub-adjacent section.

With the apparatus of the present invention, it is manifest that thepipes can be lowered without breaking the seal notwithstanding the factthat the diameter of the joints l3 are in excess of the diameter 01' thecasing 4. This is due to the fact that the gaskets 8, being made ofelastic material; will yield, under pressure of the joints, the innerwall of the gasket'dipping downwardly into the dished out portion 8 ofthe head 5. As soon as a joint clears the gasket the latter will flexinto engagement with the outer periphery of the casing immediately abovethe joint, in an apparent manner.

Various changes may be made in the details of description proportion andarrangement of parts within the scope of the claims hereto appended.

What is claimed is:

1. A method of intercepting gas in the casing of an oil or gas wellwhile welding the proximate terminals of the inner casing pipes, whichcomprises internally sealing the inner casing of the well and sealingthe space between the inner and outer casings, both seals being belowthe zone oi the welding operation.

2. A method of intercepting gas in the casing of an oil or gas wellwhile welding the proximate terminalsof the inner casing pipes, whichcomprises internally sealing said casing and also sealing the spacebetween the inner and outer well casings, the seals being initiallypositioned above gas by pass conduits in the outer casing and below thewelding zone of the inner casing.

3. A method of interceptinggas in the casing of an oil or gas wellduring a welding operation on the casing pipes comprising the employmentof means to prevent gases irom rising in the well above a predeterminedpoint, which point is below the'welding zone ofthe pipes.

4. Means to seal oil and gas well casings against the rise of gas whilewelding the inner casing'jypipes, including, in combination with a pairof concentric casings, sealing means removably mounted within the innercasing, and sealing means on the outer casing and spanning the spacetherebetween and the inner casing, said sealing means being located at apoint below the zone of welding operation.

5. Same as claim 4 in addition to which the second said sealing means isyieldable to flex under pressure of'the welded joints of the inner pipepassing therethrough.

6. In combination with concentric oiland gas well casings the inner ofwhich consists of a series of jointed pipes, means to seal the casingsagainst the rise of gas above a predetermined point in the casings,during a welding operation on the casings, comprising a seal within theinner casing, and a seal carried by the outer casing and extending intoengagement with the inner casing at the zone of the inner seal, the sealof the outer casing being flexible to yield under pressure of the pipejoints passing therethrough.

7. A step in the method of intercepting gas in the casing of an oil orgas well while welding the proximate terminals of the pipe sectionsgoing to make up the inner casing of the well which comprises internallysealing the first section at a point appreciably below its upperterminal and also sealing the space between the inner and outer wellcasings, the outer seal circumscribing the inner seal.

8. A method of sealing the casings of oil and gas wells, while weldingthe proximate terininals of the inner casing pipes, against the rise orgas from the well comprising internally sealing the first section of theinner casing preparatory to lowering said section into the outer wellcasing, the seal being located at a point remote from the upper terminalof the section, the space between the inner and outer casings being alsosealed, said latter seal being flexible to yield under pressure of theenlarged joints of the inner casing sections while the latter are beinglowered into the well through the outer casing.

EARL G. SUMMERS.

